Ryan Reynolds: The Truth About Nude Scenes

The pair, who play co-workers pretending to be an engaged couple, found themselves filming completely in the buff during a rollicking nude sequence, which started out "awkward," but ended up just being business as usual, according to Reynolds.

"Filming a scene that involves being entirely naked and takes a couple days can be a little awkward," the actor, 32, tells PEOPLE. "Thankfully you're there for so long and you're doing it for so long that you dispense with the awkwardness pretty quickly and start to have mundane, normal conversations – the difference being you're not wearing pants."

The movie's director, Anne Fletcher, was set on making the scene as funny – and realistic – as possible.

"The naked scene in the movie was a lot of fun," she tells PEOPLE. "We had a great time doing it. It was the only scene that I ended up rehearsing because I really wanted to shoot them completely naked."

Reynolds and Bullock's moves were expertly choreographed, but the rehearsals tended to get silly, says Fletcher. "We had so much fun laughing at just the possibilities of what we could get away with."

As for Bullock, she credits Reynolds with making her look good. "You know why I looked hot?" she tells Glamour magazine. "Because everyone was looking at Ryan. Our stuff was hanging in each other's faces, and we didn't care."

Asked about being a sex symbol – he also flashes his very buff bod in the Wolverine – Reynolds tells PEOPLE that all attention makes him feel shy.

"I don't really think of myself in any particular way, shape or form that involves being known as sexy," he says. "If I did, I would probably be just like a certified ass----. But for the most part, it's flattering and incredibly sweet, I think."